Single flex circuit shared by multiple cameras of a multi-camera system

This application claims benefit of priority to U.S. Provisional Application Ser. No. 63/247,723, entitled “Single Flex Circuit Shared by Multiple Cameras of a Multi-Camera System,” filed Sep. 23, 2021, and which is hereby incorporated herein by reference in its entirety.

This disclosure relates generally to a flex circuit arrangement in a multi-camera system.

The advent of small, mobile multipurpose devices such as smartphones and tablet or pad devices has resulted in a need for high-resolution, small form factor cameras for integration in the devices. Some devices may include a multi-camera system that includes cameras held in place by a bracket. In some multi-camera systems, multiple flex circuits (e.g., a respective flex circuit for each camera) are attached to one another for purposes of conveying electrical signals along desired routes.

Some cameras may incorporate optical image stabilization (OIS) mechanisms that may sense and react to external excitation/disturbance by adjusting location of the optical lens on the X and/or Y axis in an attempt to compensate for unwanted motion of the lens. Furthermore, some cameras may incorporate an autofocus (AF) mechanism whereby the object focal distance can be adjusted to focus an object plane in front of the camera at an image plane to be captured by the image sensor. In some such AF mechanisms, the optical lens is moved as a single rigid body along the optical axis of the camera to refocus the camera.

This specification includes references to “one embodiment” or “an embodiment.” The appearances of the phrases “In one embodiment” or “In an embodiment” do not necessarily refer to the same embodiment. Particular features, structures, or characteristics may be combined in any suitable manner consistent with this disclosure.

“Comprising.” This term is open-ended. As used in the appended claims, this term does not foreclose additional structure or steps. Consider a claim that recites: “An apparatus comprising one or more processor units . . . ” Such a claim does not foreclose the apparatus from including additional components (e.g., a network interface unit, graphics circuitry, etc.).

“Configured To.” Various units, circuits, or other components may be described or claimed as “configured to” perform a task or tasks. In such contexts, “configured to” is used to connote structure by indicating that the units/circuits/components include structure (e.g., circuitry) that performs those task or tasks during operation. As such, the unit/circuit/component can be said to be configured to perform the task even when the specified unit/circuit/component is not currently operational (e.g., is not on). The units/circuits/components used with the “configured to” language include hardware—for example, circuits, memory storing program instructions executable to implement the operation, etc. Reciting that a unit/circuit/component is “configured to” perform one or more tasks is expressly intended not to invoke 35 U.S.C. § 112(f) for that unit/circuit/component. Additionally, “configured to” can include generic structure (e.g., generic circuitry) that is manipulated by software and/or firmware (e.g., an FPGA or a general-purpose processor executing software) to operate in manner that is capable of performing the task(s) at issue. “Configure to” may also include adapting a manufacturing process (e.g., a semiconductor fabrication facility) to fabricate devices (e.g., integrated circuits) that are adapted to implement or perform one or more tasks.

“First,” “Second,” etc. As used herein, these terms are used as labels for nouns that they precede, and do not imply any type of ordering (e.g., spatial, temporal, logical, etc.). For example, a buffer circuit may be described herein as performing write operations for “first” and “second” values. The terms “first” and “second” do not necessarily imply that the first value must be written before the second value.

“Based On.” As used herein, this term is used to describe one or more factors that affect a determination. This term does not foreclose additional factors that may affect a determination. That is, a determination may be solely based on those factors or based, at least in part, on those factors. Consider the phrase “determine A based on B.” While in this case, B is a factor that affects the determination of A, such a phrase does not foreclose the determination of A from also being based on C. In other instances, A may be determined based solely on B.

It will also be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the intended scope. The first contact and the second contact are both contacts, but they are not the same contact.

The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description and the appended claims, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

As used herein, the term “if” may be construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” may be construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context.

Various embodiments include a camera system having multiple cameras (referred to herein as a “multi-camera system”) that are coupled to a same, shared flex circuit (referred to herein as a “single” flex circuit). It should be understood that while the term “single” is used herein to describe the aspect of multiple cameras sharing the same flex circuit, a multi-camera system may include one or more additional flex circuits (that is, in addition to the single flex circuit) in various embodiments within the scope of the present disclosure.

In various embodiments, the single flex circuit may include a first portion, a second portion, and a third portion. The first portion of the single flex circuit may be coupled with a first camera of the multi-camera system. The second portion of the single flex circuit may be coupled with a second camera of the multi-camera system. The second portion may include a service loop proximate the second camera. The third portion of the single flex circuit may include a connector for connecting the single flex circuit to one or more other components. The single flex circuit may be configured to convey electrical signals between the connector and each of the first camera and the second camera.

Compared to some other multi-camera systems that include multiple flex circuits (e.g., a respective flex circuit for each camera) and a flex-to-flex interconnect (e.g., a hot bar interconnect) to connect the multiple flex circuits, embodiments of the multi-camera systems of the present disclosure may utilize a single flex circuit to convey electrical signals between a connector each of multiple cameras. By utilizing the single flex circuit, a multi-camera system may not include a flex-to-flex interconnect. Additionally, the service loop of the single flex circuit may provide compliance to motion in multiple axes, so as to reduce reaction forces acting on the single flex circuit when positioning one camera with respect to another camera in an active alignment process.

Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that some embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments.

illustrates a schematic perspective view of an example multi-camera systemthat may include multiple cameras that are each coupled to a single flex circuit. According to various embodiments,illustrates that the multi-camera systemmay include at least a first cameraand a second camera, and the single flex circuitis shared by the first cameraand the second camera. In alternative embodiments, the multi-camera systemmay include an alternative number and/or arrangement of cameras that are each coupled to the single flex circuit.

illustrates that the multi-camera systemmay include a chassisthat is configured to receive multiple cameras, according to various embodiments. For example,illustrates that the first cameraand the second cameraare mounted in the chassis, and the chassisfixes the position of the first camerarelative to the second camera. In, the first cameraand the second cameraare fixedly mounted to the chassis.

illustrates that the single flex circuitmay have various design features, according to various embodiments. For example, the single flex circuitmay include a first portion coupled with the first cameraand a second portion coupled with the second camera. As described herein with reference to, anisotropic conductive film (ACF) attachment processes may be used, e.g., to fixedly attach the first portion of the single flex circuitto the first cameraand/or to fixedly attach the second portion of the single flex circuitto the second camera. However, it should be understood that one or more other types of attachment processes (e.g., SMT, hot bar, etc.) may be used in various embodiments. In the schematic perspective view depicted in, some areas of the single flex circuitare obscured from view by the chassis(e.g., areas of the single flex circuiton which the first cameraand the second cameraare mounted during assembly), as described further herein. With regard to the unobscured areas of the single flex circuit,illustrates that the second portion of the single flex circuit(that is coupled to the second camera) includes service loopproximate the second camera.

illustrates that the single flex circuitincludes a third portion, comprising a connectorfor connecting the single flex circuitto one or more other components (not shown). According to various embodiments, the single flex circuitmay be configured to convey electrical signals between the connectorand each of the first cameraand the second camera.illustrates that the third portion of the single flex circuit(that comprises the connector) may be located outside of the chassis, according to various embodiments.

As described herein, the second cameramay be actively aligned with the first camerausing an active alignment process, according to various embodiments. The service loopmay provide compliance to motion in multiple axes, so as to reduce reaction forces acting on the single flex circuitwhen positioning the second camerain the active alignment process, relative to reaction forces that would be acting on the single flex circuitduring the active alignment process if the single flex circuitdid not include the service loop.illustrates that the service loopmay include one or more bends, as illustrated and further described herein with respect to(which depict various examples of “accordion shaped” service loops).

illustrates a schematic top view of the example multi-camera systemdepicted in. According to various embodiments,illustrates that the multi-camera systemmay further utilize a portionof the chassisthat includes an opening (identified by dashed lines) to receive an (optional) third camera.depicts an example in which the portionof the chassisincludes such an optional third camera(that may be fixedly mounted to chassis). While not shown in the examples depicted in, in such cases, the single flex circuitmay be shared by the first camera, the second camera, and the third camera, according to some embodiments.

Thus,illustrate different views of the multi-camera systemthat includes the single flex circuitthat is shared by at least the first cameraand the second camera. In contrast to designs that utilize multiple flex circuits for each individual camera to convey electrical signals (see e.g.,), the multi-camera systemofutilize the single flex circuitto convey electrical signals between the connectorand each of the first cameraand the second camera. Additionally, as described herein, the service loopof the single flex circuitmay provide compliance to motion in multiple axes, so as to reduce reaction forces acting on the single flex circuitwhen positioning the second camera in the active alignment process.

illustrates a schematic top view of an example multi-camera systemA that includes multiple flex circuits and a flex-to-flex interconnect (e.g., a hot bar interconnect) to connect the multiple flex circuits. For purposes of comparison to the example multi-camera systemA depicted in,illustrates a schematic top view of an example multi-camera systemB that may include the single flex circuitwithout such a flex-to-flex interconnect. According to various embodiments, the multi-camera systemB depicted inmay correspond to the multi-camera systemdepicted in.

In the example depicted in, the camera systemincludes a dual camera module that is based on two single cameras, manufactured separately, with different optical characteristics. The two cameras are aligned optically individually, separately first, on individual flexesand, respectively. The two cameras are actively aligned together mechanically, and optically, during final assembly. With the dual camera module depicted in, interconnection is through individual connectorsand, respectively, or a flex-to-flex interconnect(e.g., a hot bar interconnect).

Various challenges are associated with the aforementioned design and process associated with the example depicted in. As an example, there are challenges in mechanical alignment with components manufactured separately. As another example, there are significant challenges in optical alignment with two individual cameras. As another example, there are challenges with interconnection, through separated, individual flex alignment, with hot bar interconnection between two flexes, or individual connector. As another example, there are challenges with long assembly flow, with several un-required assembly steps (e.g., bend, hot bar, etc.). Additionally, the aforementioned design and process associated with the example depicted inmay present challenges with respect to satisfying design constraints, such as size, due to use of individual flex circuits and design requirements for alignment and interconnection. Additionally, the aforementioned design and process associated with the example depicted inmay be associated with unsatisfactory electrical performance, as the cameras are powered up individually through individual flexes, and the cameras are interconnected through a connector (or hot bar soldering).

In contrast to the multi-camera systemB ofwhich utilizes multiple flexes,and the flex-to-flex interconnect, the example multi-camera systemB depicted inutilizes one flex circuit (i.e., the single flex circuit) to convey electrical signals between the connectorand each of the first cameraand the second camera. By utilizing the single flex circuit,illustrates that the example multi-camera systemB does not include a flex-to-flex interconnect as there are not multiple flex circuits to be connected.

Additionally, the service loopof the single flex circuitof the example multi-camera systemB ofmay provide compliance to motion in multiple axes, so as to reduce reaction forces acting on the single flex circuitwhen positioning the second camera in the active alignment process.

In, the example multi-camera systemB includes the (optional) third camera, which may be fixedly mounted to the chassis(as previously described herein with respect to), according to some embodiments.

Thus, the example multi-camera systemA ofand the example multi-camera systemB ofare presented for side-by-side comparison in order to illustrate various advantages associated with the present disclosure.

illustrates multiple views of various stages of a methodof producing a multi-camera system that includes a single flex circuit utilized by multiple cameras, in accordance with some embodiments. According to various embodiments, the methodmay include anisotropic conductive film (ACF) operations(with dashed lines surrounding individual operations) (and/or one or more other types of attachment processes), including a first perspective view(depicted on the left side of) of a result of performing the ACF operations. According to various embodiments, the methodmay subsequently include assembly operations(with dashed lines surrounding individual operations), including a second perspective view(depicted on the left side of) of a result of performing the assembly operations. According to various embodiments, the methodmay subsequently include chassis integration operations, including a third perspective view(depicted on the left side of) of a result of performing the chassis integration operations.

The right side of the example methoddepicted inillustrates that a (flat) flex circuit, a first camera, and a second cameramay be utilized as part of the ACF operations. According to various embodiments, the flex circuitmay correspond to a flat version of the single flex circuitdepicted in, prior to the single flex circuitunderdoing bending operations (also referred to herein as “accordion bending” operations) associated with producing the multi-camera system. According to various embodiments, the first cameradepicted inmay correspond to the first cameradepicted in, prior to assembly into the multi-camera system. According to various embodiments, the second cameradepicted inmay correspond to the second cameradepicted in, prior to assembly into the multi-camera system. The right side of the example methoddepicted infurther illustrates that a chassismay be utilized as part of the chassis integration operations. According to various embodiments, the chassisdepicted inmay correspond to the chassisdepicted in, prior to assembly into the multi-camera system.

According to various embodiments,illustrates that the ACF operationsmay include at least: a flex loading operation; a first ACF attach operation; and a second ACF attach operation.

With respect to the flex loading operation, the flex circuitin its flattened state may include at least a first ACF pad (obscured from view in) for ACF attachment of the first cameraand a second ACF pad (obscured from view in) for ACF attachment of the second camera.

With respect to the first ACF attach operation, a first type of ACF bonder may be utilized. For example, an ACF lamination operation may be performed on a particular area of a mounting side (not shown) of the first camera, and flex PnP mounting may be performed to attach the first cameraonto the first ACF pad of the flex circuit, with the ACF bonder compressing the ACF laminate material between the mounting side of the first cameraand the first ACF bond pad of the flex circuit.

With respect to the second ACF attach operation, a second type of ACF bonder may be utilized for reverse ACF bonding. For example, a reverse ACF lamination operation may involve ACF lamination onto the second ACF pad of the flex circuit, followed by alignment of a particular area of a mounting side (not shown) of the second camerawith the ACF lamination on the second ACF bond pad. A bond tool may then be utilized to compress the ACF laminate material between the mounting side of the second cameraand the second ACF bond pad of the flex circuit.

The first perspective view(depicted on the left side of) illustrates an example of a result of performing the ACF operations, according to some embodiments.

According to various embodiments,illustrates that the assembly operationsmay include at least: a reinforcement process (RIF) operationfor the first camera; an RIF operationfor the second camera; a stiffener attachment operationfor the second camera; a side fill operationfor the second camera; and one or more flex circuit bending operations.

With respect to the flex circuit bending operation(s)(also referred to herein as “accordion bending”), the methodmay include bending the (flat) flex circuitto form a particular bend design for the service loop proximate the second camera(e.g., the particular bend design for the service loop, as depicted in the side perspective view of). As described herein, the service loop proximate the second cameraprovides compliance to motion in multiple axes, so as to reduce reaction forces acting on the flex circuit when positioning the second camerain the active alignment process (as described herein with respect to the chassis integration operations), relative to reaction forces that would be acting on the flex circuit during the active alignment process if the flex circuit did not include the service loop (e.g., the area of the flex circuitproximate the second camera, as depicted in the first side perspective viewon the left side of). According to some embodiments, the flex circuit bending operation(s)may result in the service loop having a particular bend design with one or more bends (e.g., an accordion shape), as illustrated and further described herein with respect to.

The second perspective view(depicted on the left side of) illustrates an example of a result of performing the assembly operations, according to some embodiments.

According to various embodiments,illustrates that the chassis integration operationsmay include at least a dual active alignment operation.further illustrates that, according to some embodiments, the chassis integration operationsmay further include silver (Ag) and/or thermal bracket fill operation(s).

With respect to the dual active alignment operation, the methodmay include performing one or more active alignment operations to align the second camerawith the first camera, after positioning of the cameras,into the respective openings within the chassis.

With respect to the Ag and/or thermal bracket fill operation(s), the methodmay include dispensing a silver (Ag) material and/or dispensing a thermal fill material to secure the first cameraand/or the second camerato the chassis. As used herein, the Ag material may be a non-limiting example of a conductive adhesive. In various embodiments, a conductive adhesive may be used to provide an electrical ground path from the first camerato the chassisand/or from the second camerato the chassis. It should be understood that other conductive materials may be used in addition to, or instead of, the Ag material according to various embodiments within the scope of the present disclosure.

The third perspective view(depicted on the left side of) illustrates an example of a result of performing the chassis integration operations, according to some embodiments.

Thus,illustrates an example of various stages of producing a multi-camera system that includes a single flex circuit utilized by multiple cameras. The first perspective viewofdepicts an example of a result of performing the various ACF operations, as described herein. The second perspective viewofdepicts an example of a result of performing the various assembly operations, as described herein. The third perspective viewdepicts an example of a result of performing the various chassis integration operations, as described herein.

illustrates an example of various stages of a methodof producing a multi-camera system that includes a single flex circuit utilized by multiple cameras, in accordance with some embodiments. According to various embodiments, the methodmay include module level operations(with dashed lines surrounding individual operations). According to various embodiments, the methodmay include chassis level operations(with dashed lines surrounding individual operations), including two top views (depicted on the bottom of) associated with results of performing particular individual operations of the chassis level operations.illustrates that, in some embodiments, the module level operationsmay involve a first cameraand a second camera, and the chassis level operationsmay involve an (optional) third camera. For example, the first cameradepicted inmay correspond to the first cameradepicted in, the second cameradepicted inmay correspond to the second cameradepicted in, and the (optional) third cameradepicted inmay correspond to the third cameradepicted in.

According to various embodiments,illustrates that the module level operationsmay include at least: a first ACF attach operationfor a first camera; a carrier transfer operation; a second ACF attach operationfor a second camera; RIF operationsfor the first cameraand the second camera; a stiffener attachment operationfor the second camera; and one or more flex circuit bending operations.

With respect to the first ACF attach operation, a first type of ACF bonder may be utilized. For example, as previously described herein with respect to, an ACF lamination operation may be performed on a particular area of a mounting side of the first camera, and flex PnP mounting may be performed to attach the first cameraonto a first ACF pad of a (flat) flex circuit (not shown in), with the ACF bonder compressing the ACF laminate material between the mounting side of the first cameraand the first ACF bond pad of the (flat) flex circuit.

With respect to the second ACF attach operation, a second type of ACF bonder may be utilized for reverse ACF bonding. Accordingly,depicts the carrier transfer operation, which may include transferring the (flat) flex circuit from the first type of ACF bonder (after the first ACF attach operationof the first camera) to the second type of ACF bonder (e.g., a:reverse ACF bonder) prior to performing the second ACF attach operation. For example, as previously described herein with respect to, the second ACF attach operationmay involve ACF lamination onto a second ACF pad of the (flat) flex circuit (not shown in), followed by alignment of a particular area of a mounting side of the second camerawith the ACF lamination on the second ACF bond pad. A bond tool may then be utilized to compress the ACF laminate material between the mounting side of the second cameraand the second ACF bond pad of the (flat) flex circuit.

While not shown in, performing this particular subset of the module level operationsmay result in a partially-completed multi-camera system with features similar to the first perspective view(depicted on the left side of).